13.5V low side short-circuit protection with HITFET™ BTF3050TE

Open online SPICE simulator circuit link: atv_bp_13.5V_low_side_BTF3050TE_protection_SC.tsc

HITFET™ Automotive Smart Low-Side Switch BTF3050TE:
Protection Features - Short Circuit Protection

The BTF3050TE is a 50 mOhm single channel Smart Low-Side Power Switch providing embedded
protective functions. Infineon’s HITFET™ protected low-side switches drive resistive, capacitive as
well as inductive loads. The target applications of the BTF3050TE are replay replacement, small
motors and solenoids.

This circuit demonstrates the short circuit protection feature of the BTF3050TE. Many other HITFET™
devices provide similar protection features.

Once a short circuit occurs (load current exceeding current limitation trigger level IL(LIM)_TRIGGER)),
the current is limited to IL(LIM) and a logic high at pin SRP is triggered as a latched fault signal.
This SRP pin can be pulled down to a smaller voltage than the threshold VSRP(RESET) of 1.8V (typ.)
for at least 100 µs to clear the latched fault signal.

Thermal model description:
THERMAL_MODEL=1: 1s0p PCB 300\e(mm,2)
THERMAL_MODEL=2: 1s0p PCB 600\e(mm,2)
THERMAL_MODEL=3: 1s0p PCB min. footprint
THERMAL_MODEL=4: 2s2p PCB

{1. click here to set circuit parameters}
{2. click on "Run" to calculate components}
{3. click on "OK" and Simulate Transient }

{Supply voltage [V]}
Vs:= 13.5 {use 8 ... 28}

{Switching slew rate adjustment: }
R_SRP:= 58k {use 5k ... 70k}
{normal operation, see datasheet section 5.5}

{Thermal model number: }
ThermalModel:= 1 {use 1 ... 4}

{Short circuit on/off trigger time [s] }
tSC_on:= 5m {use 1m ... 10m}
tSC_off:= 10m {use tSC_on ... 15m}

{Do not change values below.}
{Fault condition reset trigger time calculation}
tFault_reset_on:= tSC_off+2m
tFault_reset_off:= tFault_reset_on + 0.1m